Anchorage for securing structural parts to concrete bases



F. BIRCH Jul 11, 1939.

ANCHORAGE FOR SECURING STRUCTURAL PARTS TO CONCRETE BASES Filed Aug. 30, 1938 Fig; 8.

irmmasr Patented July 11, 1939 iJNITED STATES PATENT OFFIQEEL Frank Birch, Bolton, England Application August 30 In Great Britain August 24, 193 7 1 Claim.

This invention has reference to devices for securing parts of structures to concrete floors and walls.

It is often necessary to secure to concrete floors and walls part of the structure, such as for instance a wood floor above the concrete fioor, or panels on a wall, and to this end securing means have been provided which have been embedded in the un-set concrete with parts projecting above or beyond the concrete surface to which a further member, such as a joist has been secured later, and when the work is ready to be proceeded with. These projections, particularly when on a floor are frequently damaged before they are covered by being put to their proper use, and when they are damaged, it is difficult to repair them or to replace them owing to their being held firmly in the concrete.

This invention has for its object to provide means whereby the foregoing objections are overcome and which will in addition act as a strengthening means to the floor or wall.

According to this invention a device for securing parts of structures to concrete fioors and walls is in the form of a metal tray having upturned and inwardly inclined sides providing the required depth of the tray, the bottom and sides having holes or keying portions or members, whereby when the tray is sunk or embedded in the unset concrete it will provide a dove-tail shaped cavity into which a further member may be inserted and secured by concrete or cement. poured or filled in about it and inside the tray.

The invention is more particularly set forth with reference to the accompanying drawing wherein- Fig. 1 is a side elevation of a tray according to the invention.

Fig. 2 is a plan.

Figs. 3 and 4 are similar views of modified forms.

Figs. 5 and 6 are side elevations of further modified forms.

Fig. 7 is a side elevation of a tray with a detachable cover and Fig. 8 is a sectional elevation of a tray in place in concrete.

The device as shown in the drawing is made from sheet metal of square shape though it may be circular or other shape and holes 9 are made at intervals in the metal, the edges are turned up and bent inward to form sides 10, the vertical depth from the top edge of the sides to the bottom of the tray being made sufficient for the particular purpose for which the tray is intended.

When the fioor or wall is being made the trays are inserted in the floor as shown in Fig. 8 or they may be laid on the fioor when made to a certain level the remainder of the floor being built up round them. The trays are conveniently filled with some easily removable substance such as wood-wool or paper which, while allowing some of the surrounding concrete to enter the holes, prevents it from filling the tray even if it is thin enough to do so, which is not likely or alternatively a thin metal cap or cover ll may be used. In this way the tray is wholly below the floor level and the filling can be left in, or the cap H can be left on, to prevent dirt or foreign matter from entering, consequently when it is desired to secure another member to it, such as a joist support, it is only necessary to remove the filling or the cap or cover I l and insert the other member and fix it in place by packing cement or concrete into the unoccupied part of the tray. This packing keys with the concrete which has issued through the holes 9 and if in drying the external concrete should have shrunk slightly from the tray the internal concrete will to some extent pass through the holes outwardly and enter the gapQthus closing it. Even if this does not occur the tray is locked in the concrete owing to its inwardly inclined sides.

As an additional means of holding the device against movement in the concrete, the sides ill may be provided as shown in Figs. 3 and 4 with pocket-like bulges 12 which are filled with the concrete outside and prevent any upward movement of the tray. An alternative or additional holding means is shown in Fig. 5 where a rag-- bolt I3 is shown projecting downwardly so that when it is embedded in the concrete it will not be possible to lift the tray.

In Fig. 6 a modification is shown which may be used with any embodiment of the device. In this arrangement the tray has legs 94 on which it can be stood on a floor or support above which the concrete has to be filled in, the arrangement ensuring that all the trays in one floor will thus be at the same height above the supporting floor or tiles.

If desired a number of trays may be slung on a steel rod passing through the holes 9 in the sides so that the levelling will be made easier and more exact and the inserting of the trays in the concrete will be easier; the steel rods will also act as re-inforcing means for the floor.

The trays may be inserted in concrete bricks or blocks so that the bricks or blocks themselves can be built into a structure with the trays in place.

It will be understood that the angle of the sides may be varied and the sides may be only slightly inclined inwards.

What I claim as my invention and desire to secure by Letters Patent is:

An anchorage supporting tray for concrete foundations, comprising a tray having a relative- 1y large fiat bottom whereof the side edges comprise inturned flanges arranged in converging relation towards the top of the tray, the top of the tray being open, and the side flanges having struck out portions therein open at their top edges to receive concrete therethrough for passage to the interior of the tray, said struck out portions providing shoulder abutments for concrete and anchoring the tray against shifting movement when embedded in the foundation, and the bottom of said tray being provided with apertures to receive concrete therethrough.

FRANK BIRCH. 

